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Homotopy Analysis method for Solving Biological Population model

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Communications in Theoretical Physics 2011年第11期56卷 797-800页

作者： a.a.m.arafa S.Z.Rida H.mohamed Department of mathematics Faculty of ScienceSouth Valley University

In this paper,the homotopy analysis method (HAm) is applied to solve generalized biological *** fractional derivatives are described by Caputo's *** method introduces a significant improvementin this field over existing *** obtained using the scheme presented here agree well with the analyticalsolutions and the numerical results presented in Ref.[6].However,the fundamental solutions of these equations stillexhibit useful scaling properties that make them attractive for applications.

关键词： biological populations model fractional calculus homotopy analysis method mittag-Leffier function

Solving Nonlinear Fractional Differential Equation by Generalized mittag-Leffler Function method

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Communications in Theoretical Physics 2013年第6期59卷 661-663页

作者： a.a.m.arafa Z.Rida A.A.mohammadein H.m.Ali Department of mathematics and Computer Science Faculty of Science Port Said University Department of mathematics Faculty of Science South Valley University Department of mathematics Faculty of Science Aswan University

In this paper, we use mittag-Leffler function method for solving some nonlinear fractional differential equations. A new solution is constructed in power series. The fractional derivatives are described by Caputo's se... 详细信息

关键词： nonlinear fractional differential equations mittag-Leffler function Caputo fractional derivative

Structural damage assessment criteria for reinforced concrete buildings by using a Fuzzy Analytic Hierarchy process

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Underground Space 2018年第3期3卷 243-249页

作者： Khader m.Hamdia mohammed arafa mamoun Alqedra Institute of Structural mechanics Bauhaus-Universitat Weimar99423 WeimarGermany Department of Civil Engineering The Islamic University of GazaGazaPalestine

Reinforced concrete structures are often exposed to many types of damages and deteriorations due to different causes and exposure conditions during their life *** of such structures is inherently subjected to uncertainty and ambiguity,where subjective opinion and incomplete numeric data are *** the damage assessment process,estimating the importance of assessment criteria is an important field in itself,and depends heavily on the experience and expertise of *** aim of this study is to present a fuzzy-based assessment model,which estimates the importance of structural assessment criteria for concrete *** work aims also at studying,identifying,and prioritizing assessment *** assessment criteria are based on close visual inspections and simple measurements that do not require special testing or long-term *** main assessment criteria include the state of building history,environmental conditions,structural capacity,durability,and professional involvement in *** of them has two levels of *** criteria weights are obtained based on the opinions of experts using the Fuzzy Analytic Hierarchy Process(FAHP)*** application of the FAHP method showed that the most important criteria is the structural capacity with a weighting factor of 50.1%,followed by the environmental condition as second,with a weighting factor of 22.5%.

关键词： Assessment criteria Uncertainty Fuzzy logic Analytic hierarchy process Building evaluation

Peltier Coefficient and Photon-Assisted Tunnelling in Quantum Point Contact

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Chinese Physics Letters 2008年第12期25卷 4399-4401页

作者： arafa H. Aly Department of Physics Zaragoza University Zaragoza 50009 Spain Department of Physics Inha University 402-751 South Korea Department of Physics Faculty of Sciences Beni-Suef University Egypt

We present the Peltier coefficient and thermal transport in quantum point contact （QPC）, under the influence of external fields and different temperatures. Also we obtain the oscillations of the Peltier coefficient in external fields. Numerical calculations of the Peltier coefficient are performed at different applied voltages, amplitudes and temperatures. The obtained results are consistent with the experimental data in the literature.

关键词： field emission molybdenum dioxide enhancement factor

Numerical damage evaluation of perforated steel columns subjected to blast loading

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Defence Technology（防务技术） 2022年第5期18卷 735-746页

作者： mahmoud T.Nawar Ibrahim T.arafa Osama m.Elhosseiny Structural Engineering Department Zagazig UniversityZagazig44519Egypt

The structural performance of perforated steel columns(PSCs)is significantly more complex than the one of solid web I-shaped elements under the diversity of blast loading *** damage criterion of PSCs is not only related to initial deformation response during the blast but also the residual axial load capacity and it can be considered as a reliable index after the blast ***,the PSCs damages will be studied in two stages;direct and post blast *** the present study,the dynamic response of PSCs was numerically evaluated under different levels of blast threats using LS-DYNA *** explicit finite element(FE)analyses are carried out to investigate the effect of various parameters,such as web opening shapes,boundary conditions and strengthening details on the damage index and toughness of the PSCs compared to the parent steel *** results of the comparative study show that the damage and toughness decrease when the support condition changes from pinned to fixed ends through the two stages of *** give high toughness compared to its parent sections during blast shock stage while,a remarkable decrease in toughness is observed during the application of axial gravity after blast ***,the web opening shapes have slight effects on the global dynamic behavior of PSCs,particularly in terms of residual *** the contrary,the retrofitting strategy using both closed holes at end and vertical stiffeners have an effective enhancement to get higher toughness in case of the extreme blasts.

关键词： Perforated steel columns Blast load Damage criterion Numerical modeling Explicit finite element analysis Web-opening shapes

With increasing trends of prostate cancer in the Saudi Arabia and Arab World: Should we start screening programs?

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World Journal of Clinical Oncology 2017年第6期8卷 447-449页

作者： mostafa A arafa Danny m Rabah College of medicine King Saud University Department of Surgery College of Medicine King Saud University

Incidence rate for prostate cancer in the Arab World is significantly lower than United States and Europe, it ranges from 5.5% to 39.2%. However, the incidence and the number of deaths is expected to increase. In Saudi Arabia, the crude incidence rate and age standardized incidence rate of prostate cancer are reported to be steadily increasing in between 2001-2008. Only two screening trials were attempted in 2001 and 2009 which yielded an incidence rate of 1.17% and 2.5% respectively. men in the Arab world are sharing a common characteristic of poor knowledge and poor attitude towards prostate cancer examination and screening practices. They are ill-informed about the PSA test's strengths and drawbacks because the doctors are not talking to them about the importance of counselling. men should be encouraged to do PSA testing before the age of 50 and till the age of 70 years. This could be achieved by enhancing their attitude and enriching the knowledge of the physicians towards PSA testing, harms and benefits, through shared decision making, which would increase men's knowledge scores, reduced their decisional conflict and promote greater involvement in decision making.

关键词： Prostate cancer Incidence Arab World Screening

mineralogy and geochemistry of fine-grained Dahab stream sediments, Southeastern Sinai, Egypt: emphasis on the intergrowths of Fe–Ti oxides

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Acta Geochimica 2021年第6期40卷 871-894页

作者： Adel A.Surour Ahmed.m.A.El-Kammar Ebtisam H.arafa Hala m.Korany Petroleum and mining Geology Faculty of SciencesGalala University43511 New Galala CityEgypt Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt

mineralogical and geochemical characteristics of stream sediments collected from 30 stations in the Dahab-Wadi Kid area(southeastern Sinai,Egypt)are *** studied sediments contain considerable amounts of heavy minerals,including abundant Fe–Ti oxides,with up to 25.94%index figure that measures the relative abundance of heavy minerals to light *** of the sediments and nature of Fe–Ti oxide intergrowths,in addition to some non-opaque heavy minerals,indicate multiple provenances with contributions from a variety of Neoproterozoic mafic to felsic *** amounts of heavy minerals are derived from schists that belong to the so-called Wadi Kid volcanosedimentary *** to the considerable contribution of the felsic intrusions represented by within-plate granites,the sediments are enriched in REE-bearing minerals(e.g.,monazite,cerianite,La-cerianite and allanite),V-bearing thorite,zircon,and a ZrO_(2) *** majority of Fe–Ti oxides are derived from the mafic intrusions,and they show evidence of pre-,syn-and post-depositional phases of alteration and formation of *** to the geochemical signature of the bulk silt fraction,there is remarkable enrichment of LREEs with distinct negative Eu anomaly,and this supports dominance of a provenance dominated by felsic intrusions(i.e.,the A-type within-plate granite and associated pegmatites).Also,the felsic provenance is responsible for slight abnormality of ∑PU+Th content(up to~37 ppm)and few anomalous samples bear uraniferous zircon and Ce-type *** present paper sheds light on the fertility of the Dahab stream sediments in some economic minerals for possible future exploitation,not for gold only,but for potential REEbearing minerals that are needed for a wide spectrum of modern technological industries.

关键词： Dahab stream sediments Silt fraction Fe-Ti oxides Textural variations Rees enrichment

Design, Sonosynthesis, Quantum-Chemical Calculations, and Evaluation of New mono-and Bis-pyridine Dicarbonitriles as Antiproliferative Agents

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Chinese Journal of Chemistry 2020年第5期38卷 501-508页

作者： Wael Abdelgayd Ahmed arafa modather F.Hussein Chemistry Department College of ScienceJouf UniversityP.O.Box 2014SakakaAljoufKingdom of Saudi Arabia Chemistry Department Faculty of ScienceFayoum UniversityP.O.Box 63514Fayoum CityEgypt Chemistry Department Faculty of ScienceAl-Azhar UniversityAsyut branchEgypt

A highly efficient,simple,and clean single-step sonosynthetic procedure has been sophisticated for assembling new series of mono-and bis-pyridine dicarbonitriles from ketones,HCl,and *** presented protocol is applicable for the preparation of a broad range of uniquely substituted pyridine dicarbonitriles and seems to be superior in comparison with other previously reported *** antiproliferative impact of the newly synthesized derivatives was screened towards three representative cancer cell lines(mCF-7,A549,and HCT116).most of the evaluated derivatives showed a moderate to excellent anti-proliferative activity towards the selected cell *** these,compounds 4h,4k,10,12a,and 12b showed both potent anticancer activity(ICs0m)and lower cytotoxic effect(ICs0>58μm)on non-tumorigenic cells(mCF-10A and NCm460),suggesting their promising potential to be lead molecules for future antitumor drug *** structure-activity relationships have been also ***,quantum chemical studies based on Density Functional Theory(DFT)of the synthesized compounds were investigated and found to be consistent with the in vitro inhibitory activities.

关键词： pyridine nitrile synthesis

A fractional-order model of HIV infection： Numerical solution and comparisons with data of patients

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International Journal of Biomathematics 2014年第4期7卷 23-33页

作者： A. A. m. arafa S. Z. Rida m. Khalil Department of mathematics and Computer Science Faculty of Sciences Port Said University Port Said Egypt Department of mathematics Faculty of Sciences South Valley University Qena Egypt Department of mathematics Faculty of EngineeringOctober University for modern Sciences and Arts (mSA University) 6th Oct. City Giza Egypt

In this paper, a fractional-order model which describes the human immunodeficiency type-1 virus （HIV-1） infection is presented. Numerical solutions are obtained using a generalized Euler method （GEm） to handle the fractional derivatives. The fractional derivatives are described in the Caputo sense. We show that the model established in this paper possesses non-negative solutions. Comparisons between the results of the fractional-order model, the results of the integer model and the measured real data obtained from 10 patients during primary HIV-1 infection are presented. These compar- isons show that the results of the fractional-order model give predictions to the plasma virus load of the patients better than those of the integer model.

关键词： Fractional calculus Euler method HIV model numerical results.